assume cs:code ds: data  ss: stack

data segment 
    db 'ibm             '
    db 'dec             '
    db 'dos             '
    db 'vax             '

data ends

stack segment
     dw 0,0,0,0,0,0,0,0
stack ends



code segment
start: mov ax,data
       mov ds,ax
       mov ax,stack
       mov ss,ax
       mov sp,16
       mov bx,0
       mov cx,4

s:     push cx
       mov si,0
       mov cx,3
s0:    mov al,[bx+si]
       and al,11011111b
       mov [bx+si],al
       inc si
       loop s0
       add bx,16
       pop cx
       loop s

       mov al,[bx+si]
       mov bx,[]
  mov ax,4c00h
  int 21h

code ends 
end start 



